A sensor assembly having a two-dimensional array sensor and an imaging optics is used to obtain an infrared two-dimensional image. In recent years, costs of sensor assemblies have been reduced so that the sensor assemblies can be included in consumer electronics devices such as air conditioners.
Patent Literature (PTL) 1 discloses a technique for obtaining a two-dimensional image by causing a line sensor to perform scanning, with a goal of reducing costs of sensor assemblies.
Patent Literature (PTL) 2 discloses an imaging optics including a lens made of silicon or germanium.